Login to Spotfire 7.9 SSO with Kerberos Through Reverse Proxy outside Domain

Hi Everyone,


Recently we've installed a Spotfire Server  v7.9 configured with Kerberos Single Sign on. Login with SSO inside Enterprise network is working like a charm. But when the user comes via Reverse Proxy server outside enterprise network without a Domain info, browser shows a Windows authentication form to accept credentials. Since the user is not in domain, it does not authorize to continue. 

There were the solutions like using a VPN, implementing an external authentication system etc. But none of them is efficient to use in the organization. 


There is another BI solution which is handling the user authentication requests when they are outside organization via a logonNoSSO(.html, .jsp like) page.


Does anybody ever used a function in Spotfire (noSSOlogon page)? Do you have any suggestions to manage users trying to login outside enterprise network (especially mobile users)?


Kind Regards,